Created: May 25, 2016
No description available.
There are several embedded projects that uses timer as part of its system. It is one of the simplest circuits that can be built with few parts. This project features a simple counter that uses PIC microcontroller as its main component. A 0 to 99 minutes countdown timer that specifically uses PIC16F628A having 16 I/O pins with individual direction control. Also, it has an analog comparator module with two analog comparators. In addition, this circuit uses 4MHz external crystal to provide the necessary clock to correctly display the time with an LCD.
The countdown timer uses components such as PIC microcontroller, an LCD and push button switches. One button is for Start/Stop function and the other 2 buttons for units & tens counting. The circuit is wired in such a way that the user will have to select the limit of counting initially. For an instance, if the user is interested in counting up to 9 minutes only, then he is supposed to press the unit’s button alone. Pressing the tens button along with the unit’s button will allow the counting from 1 to 99 minutes. Once the limit has been set, a Start/Stop button should be pressed to start or stop the timer.
The device has a wide range of applications that can be used in appliances and other gadgets that needs a timer to optimize its functionality. This can be observed in ovens, traffic lights and other digital devices for synchronization especially for embedded systems.